<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>双飞翼布局</title>
  <style>
    * {
      padding: 0;
      margin: 0;
    }
    .header {
      width: 100%;
      height: 30px;
      background: aquamarine;
    }
    .main {
      overflow: hidden;
    }

    .main .center {
      width: 100%;
      float: left;
    }

    .main .center .center-inner {
      width: auto;
      height: 300px;
      background: aliceblue;
      margin: 0 100px;
    }

    .main .left {
      background: palegoldenrod;
      width: 100px;
      height: 300px;
      float: left;
      margin-left: -100%;
    }
    .main .right {
      background: lightpink;
      width: 100px;
      height: 300px;
      float: left;
      margin-left: -100px;
    }

    .footer {
      width: 100%;
      height: 30px;
      background: #aae997;
    }
  </style>
</head>
<body>
<div class="header">Header</div>
<div class="main">
  <div class="center">
    <div class="center-inner">
      <p>Hello world</p>
    </div>
  </div>
  <div class="left">left</div>
  <div class="right">right</div>
</div>
<div class="footer">Footer</div>
</body>
</html>
